Buggy code:
public class Transformer { private static String configFile ; private static final Logger log4j = LogManager . getLogger ( Transformer . class . getName ( ) ) ; public static void main ( String [ ] args ) { Transformer . configFile = "config.properties" ; if ( ( args . length ) > 0 ) { Transformer . configFile = args [ 0 ] ; } Transformer . log4j . info ( ( ( "Reading<seq2seq4repair_space>configfile<seq2seq4repair_space>'" + ( Transformer . configFile ) ) + "'" ) ) ; ConfigFileReader . readFile ( Transformer . configFile ) ; if ( ! ( ConfigFileReader . isFileValid ( ) ) ) return ; String dburl = ( ( "jdbc:" + ( ConfigFileReader . getRelationalDatabaseType ( ) ) ) + ":////" ) + ( ConfigFileReader . getRelationalDatabasePath ( ) ) ; String dbName = ConfigFileReader . getRelationalDatabaseName ( ) ; String user = ConfigFileReader . getRelationalDatabaseUser ( ) ; String pwd = ConfigFileReader . getRelationalDatabasePassword ( ) ; String tableNames = ConfigFileReader . getTableNames ( ) ; Transformer . log4j . info ( ( ( ( ( "Using<seq2seq4repair_space>Relational<seq2seq4repair_space>Database:<seq2seq4repair_space>" + dburl ) + dbName ) + ",<seq2seq4repair_space>Graph<seq2seq4repair_space>Database:<seq2seq4repair_space>" ) + ( ConfigFileReader . getGraphDatabasePath ( ) ) ) ) ; DatabaseReader reader = new DatabaseReader ( dburl , dbName , user , pwd , tableNames ) ; GraphDatabaseService graphDb = null ; try { graphDb = new GraphDatabaseFactory ( ) . newEmbeddedDatabase ( ConfigFileReader . getGraphDatabasePath ( ) ) ; } catch ( RuntimeException e ) { Transformer . log4j . error ( ( "Could<seq2seq4repair_space>not<seq2seq4repair_space>connect<seq2seq4repair_space>to<seq2seq4repair_space>GraphDB<seq2seq4repair_space>" + ( ConfigFileReader . getGraphDatabasePath ( ) ) ) ) ; e . printStackTrace ( ) ; return ; } Transformer . log4j . info ( "Transaction<seq2seq4repair_space>to<seq2seq4repair_space>Neo4j<seq2seq4repair_space>DB..." ) ; int nodeCounter = 0 ; int relCounter = 0 ; int constCounter = 0 ; try ( Transaction tx = graphDb . beginTx ( ) ) { graphDb . execute ( "MATCH<seq2seq4repair_space>(n)<seq2seq4repair_space>OPTIONAL<seq2seq4repair_space>MATCH<seq2seq4repair_space>(n)-[r]-()<seq2seq4repair_space>DELETE<seq2seq4repair_space>n,r" ) ; tx . success ( ) ; Transformer . log4j . info ( "cleaned<seq2seq4repair_space>graphDB<seq2seq4repair_space>from<seq2seq4repair_space>existing<seq2seq4repair_space>nodes<seq2seq4repair_space>and<seq2seq4repair_space>relationships" ) ; } catch ( Exception e ) { Transformer . log4j . error ( "Could<seq2seq4repair_space>not<seq2seq4repair_space>perform<seq2seq4repair_space>statement<seq2seq4repair_space>for<seq2seq4repair_space>deleting<seq2seq4repair_space>all<seq2seq4repair_space>existing<seq2seq4repair_space>nodes" ) ; e . printStackTrace ( ) ; } try ( Transaction tx = graphDb . beginTx ( ) ) { for ( String del : reader . getDeleteStatements ( ) ) { try { graphDb . execute ( del ) ; System . out . println ( del ) ; } catch ( Exception e ) { <START_BUG> System . out . println ( ( del + "<seq2seq4repair_space>konnte<seq2seq4repair_space>nicht<seq2seq4repair_space>ausgeführt<seq2seq4repair_space>werden" ) ) ; <END_BUG> } } tx . success ( ) ; } catch ( Exception e ) { e . printStackTrace ( ) ; } Transformer . log4j . info ( "cleaned<seq2seq4repair_space>graphDB<seq2seq4repair_space>from<seq2seq4repair_space>existing<seq2seq4repair_space>constraints" ) ; try ( Transaction tx = graphDb . beginTx ( ) ) { for ( String cons : reader . getConstStatements ( ) ) { try { System . out . println ( cons ) ; graphDb . execute ( cons ) ; constCounter ++ ; } catch ( Exception e ) { e . printStackTrace ( ) ; } } tx . success ( ) ; } catch ( Exception e ) { e . printStackTrace ( ) ; } try ( Transaction tx = graphDb . beginTx ( ) ) { for ( String node : reader . getNodeStatements ( ) ) { System . out . println ( node ) ; graphDb . execute ( node ) ; nodeCounter ++ ; } for ( String rel : reader . getRelStatements ( ) ) { graphDb . execute ( rel ) ; System . out . println ( rel ) ; relCounter ++ ; } tx . success ( ) ; } Transformer . log4j . info ( "Transaction<seq2seq4repair_space>done" ) ; Transformer . log4j . info ( ( ( ( ( ( constCounter + "<seq2seq4repair_space>Constraints,<seq2seq4repair_space>" ) + nodeCounter ) + "<seq2seq4repair_space>Nodes<seq2seq4repair_space>and<seq2seq4repair_space>" ) + relCounter ) + "<seq2seq4repair_space>Relationships<seq2seq4repair_space>created" ) ) ; } }

Fix:
System . out . println ( ( del + "<seq2seq4repair_space>konnte<seq2seq4repair_space>nicht<seq2seq4repair_space>ausgefuehrt<seq2seq4repair_space>werden" ) ) ;